Glaciers presently contain ~75% of Earths freshwater
Greenland and Antarctica
If the Antarctic ice cap melted:
sea level would rise >200 feet
Sea level changes cause shoreline shifts
How to make a glacier?
Insufficient summer melting
How to make
In Wyoming, west of the Black Hills of SD
Two main types of Igneous Rocks
formed from magma
formed from lava
Igneous rock names.
are based on texture and composition
Some lead-in concepts
1: Earth is differentiated (core-mantle-crust)
2: Crust is very thin
3: Continental crust is granitic (avg density 2.7 g/cm3)
Oceanic crust is basaltic (avg density 3.0 g/cm3)
4: Earth has an asthenosphere
Crustal Deformation Cause:
How can rocks bend?
You can take the single bar
of hard toffee in this box
and quickly snap it in half
Changed rocks. from heat and pressure
Heat and pressure from being deep, or from tectonic squeezing
Guess what? There are two subgroups
Having planar attributes
Lacking planar .
The Foliated Series
With increasing m
Field trip to Tanque Verde this Saturday!
8:00 AM departure; loading dock
In brittle regime:
joints, tensile fractures,
The photograph in the previous slide was borrowed from an earlier version of a
Tarbuck & Lutens textbook because of its value of making the following point:
Mass wasting affects peoples lives!
The downslope movement of Earth material due to g
Origin of the Solar System
The Nebular Hypothesis for the origin of the Solar System
was developed in the 18th century
Immanuel Kant 1775
Pierre Laplace 1796
Today, weve simply added details and refer to it as
The Nebular Model
A) There is raw material in
Geology 101Lesson 2 Assignment
1. What is meant by "hydrogen is the simplest of all elements"?
Hydrogen is called the simplest of all elements because its atomic number is one. This means
that it has only one proton and one electron. Furthermore, mo
Calendar indicating deadlines for course elements in Geol 101 online, summer 2016
May 16 Survey due
May 17 Quiz about
Syllabus and Policies
Assignment A due
Lesson 1 quiz due
Lesson 2 quiz due
Earth Materials: Minerals and
The only record of Earths history is that
contained in rocks.
Kind of rock formed at a given place and time reveals
conditions on Earth at that place and time.
Some rocks (esp. sedimentary rocks) contain fossils.
Geology of the
Late Paleozoic Era
408-360 M.Y. ago
Elapsed time = 48 M.Y.
1% of Earth history
Plate tectonic history in the east
(Appalachian Mobile Belt):
Geology and Life of the Archean
4.6 2.5 B.Y. ago.
Elapsed time = 2.1 B.Y
~46% of Earth history
Archean geologic history difficult to work
Few useful fossils, so hard to find time lines.
Many rocks formed in Archean were melted
Interpretation of Sedimentary Rocks
Sed. rx. important because they:
Contain record of local surface/near-surface
conditions, processes at time seds formed.
May contain fossils that:
Provide paleoenvironmental info (Earth history)
Allow relative dati
Rocks, Fossils and Time
Which is the oldest rock shown?
Stratum = layer of sedimentary rock (plural = strata). Also
called a bed, or layer.
Stratigraphy = study of sedimentary rock layers
Dynamic Earth Models: Continental
Drift and Plate Tectonics
"Continental Drift" Model
Early in 20th century, Alfred
Wegener, others, assembled
evidence the continents had
been connected in a giant
Pangaea) and had later
Geologic Time: Concepts and
Relative Age Dating
Relative Versus Absolute Time
Relative dating-sets out events in the order
in which they occurred
based on position in rock record
Absolute dating-timing of geologic events
is referred to in ye
Rocks, Fossils and Time
Part 2Fossils, Fossilization and
Fossils and Fossilization
Fossil-remains of organism from geologic
past, preserved in rock or sediment.
Fossilization-natural processes by which
remains of organisms are prese
Meanings of Evolution
(1) Fact that life on Earth has changed over time.
Is clear from fossils in sedimentary rock record.
Fossils in older rocks differ from fossils in younger rocks.
Not based on any theory.
Known before Darwin was born.
Geology and Life of the
2.5 BY - 550 MY ago
Elapsed time = 2 BY
42% of Earth history
very few greenstone belts & granite-gneiss terranes;
most Proterozoic rocks less deformed than Archean
structures of mountain belts similar t
Geology of the Early
Cambrian, Ordovician and
And the seas came in and the seas
~545 - 505 Million Years Ago
Elapsed Time = 40 Ma
0.9% of Earth history
Major trends of the Cam
Geology as a Science
Geology is the science concerned with the
To study Earth, geologists use elements of:
Two main subdivisions:
Physical geologystudy of:
Earth materials (minerals and rocks)
Life of the Paleozoic Era:
All 5 Kingdoms of life present.
Nearly all major marine phyla
present, except Phylum Bryozoa
(bryozoans) and Phylum Cnidaria
Essentially all life was in oceans.
Algae in rivers, lakes,
Rocks, Fossils and Time
Principles and Concepts (2)
Thus far, we have seen that:
Basic geometric principles allow us to do local and regional relative age
dating of rocks (put events in the order in which they occurred): Stenos
Laws, Huttons Laws.
Exam 2 Multiple Choice:
identify the choice that best completes the statement or answers the question.
a” 1. The breakdown of exposed rook into small fragments and dissolved ions is termed
C/ 2. Grains become ro